Desiigner on Cops' Radar After Exposing Himself During Meltdown

Desiigner was caught on video exposing himself twice during a heated argument … and now cops wanna have a chat with him … TMZ has learned.

Law enforcement sources tell TMZ … the rapper got into a traffic dispute with another driver behind him. You can see in the video the other driver calls Desiigner a homophobic slur before the rapper confronts him and exposes himself twice, yelling “Suck my d***.”